English: All points in the gray area are concordant and all points in the white area are discordant with respect to point <math>(X_1, Y_1)<\math>. With <math>n=30<\math> points, there are a total of <math>\binom{30}{2} = 435<\math> possible point pairs. In this example there are 395 concordant point pairs and 40 discordant point pairs, leading to a Kendall rank correlation coefficient of 0.816.